Anti-Corrosion Properties of Polyaniline Coating on X70 Steel

In this paper,the anticorrosion properties of polyaniline coating on X70 steel in acid (5% HNO3 ),weak alkaline (saturated Na2CO3),alkaline (5% KOH) solution were studied by using polarization and AC impedance technique. The results showed that polyaniline coat had an obvious anticorrosive effect on X70 steel in all these three kinds of solutions,and in a short period of time,polyaniline in acidic solution showed the best anticorrosive properties. In addition,saturated Na2CO3 solution was used to simulate the soil environment,so that we could study the changing discipline of X70 steel electrode covered with polyaniline film. Polarization and AC impedance analysis showed that polyaniline had perdurable anticorrosive properties to X70 steel,and its anticorrosive mechanism should be polyaniline's shielding and protective effect on the anode (passive role).